game of life

This required me to figure out some unicode-related nuances, but no new
primitives.

3 files changed, 204 insertions, 1 deletions

diff --git a/life.teliva b/life.teliva
new file mode 100644
index 0000000..788125e
--- /dev/null
+++ b/life.teliva
@@ -0,0 +1,201 @@
+os.setlocale("en_US.UTF-8")
+window = curses.stdscr()
+
+
+-- animation-based app
+window:nodelay(true)
+
+function sleep(a)
+    local sec = tonumber(os.clock() + a);
+    while (os.clock() < sec) do
+    end
+end
+
+
+-- grid data structure
+lines, cols = window:getmaxyx()
+
+grid = {}
+for i=1,lines*4 do
+  grid[i] = {}
+  for j=1,cols*2 do
+    grid[i][j] = 0
+  end
+end
+
+
+-- grab a 4x2 chunk of grid
+function grid_char(line, col)
+  result = {}
+  for l, row in ipairs({unpack(grid, (line-1)*4+1, line*4)}) do
+    result[l] = {unpack(row, (col-1)*2+1, col*2)}
+  end
+  return result
+end
+
+function print_grid_char(window, x)
+  result = {}
+  for l, row in ipairs(x) do
+    for c, val in ipairs(row) do
+      window:mvaddstr(l, c, val)
+    end
+  end
+  return result
+end
+
+-- testing for grid_char
+--? grid = {
+--?         {1, 2, 3, 4},
+--?         {5, 6, 7, 8},
+--?         {9, 10, 11, 12},
+--?         {13, 14, 15, 16},
+--?       }
+--? for l, row in ipairs(grid_char(1, 1)) do
+--?   print(l, row)
+--?   for c, val in ipairs(row) do
+--?     print(l, c, val)
+--?   end
+--? end
+
+
+-- look up the braille pattern corresponding to a 4x2 chunk of grid
+-- https://en.wikipedia.org/wiki/Braille_Patterns
+-- not obviously programmatic because Unicode added 4x2 after 3x2
+glyph = {
+  0x2800, 0x2801, 0x2802, 0x2803, 0x2804, 0x2805, 0x2806, 0x2807,   0x2840, 0x2841, 0x2842, 0x2843, 0x2844, 0x2845, 0x2846, 0x2847,
+  0x2808, 0x2809, 0x280a, 0x280b, 0x280c, 0x280d, 0x280e, 0x280f,   0x2848, 0x2849, 0x284a, 0x284b, 0x284c, 0x284d, 0x284e, 0x284f,
+  0x2810, 0x2811, 0x2812, 0x2813, 0x2814, 0x2815, 0x2816, 0x2817,   0x2850, 0x2851, 0x2852, 0x2853, 0x2854, 0x2855, 0x2856, 0x2857,
+  0x2818, 0x2819, 0x281a, 0x281b, 0x281c, 0x281d, 0x281e, 0x281f,   0x2858, 0x2859, 0x285a, 0x285b, 0x285c, 0x285d, 0x285e, 0x285f,
+  0x2820, 0x2821, 0x2822, 0x2823, 0x2824, 0x2825, 0x2826, 0x2827,   0x2860, 0x2861, 0x2862, 0x2863, 0x2864, 0x2865, 0x2866, 0x2867,
+  0x2828, 0x2829, 0x282a, 0x282b, 0x282c, 0x282d, 0x282e, 0x282f,   0x2868, 0x2869, 0x286a, 0x286b, 0x286c, 0x286d, 0x286e, 0x286f,
+  0x2830, 0x2831, 0x2832, 0x2833, 0x2834, 0x2835, 0x2836, 0x2837,   0x2870, 0x2871, 0x2872, 0x2873, 0x2874, 0x2875, 0x2876, 0x2877,
+  0x2838, 0x2839, 0x283a, 0x283b, 0x283c, 0x283d, 0x283e, 0x283f,   0x2878, 0x2879, 0x287a, 0x287b, 0x287c, 0x287d, 0x287e, 0x287f,
+
+  0x2880, 0x2881, 0x2882, 0x2883, 0x2884, 0x2885, 0x2886, 0x2887,   0x28c0, 0x28c1, 0x28c2, 0x28c3, 0x28c4, 0x28c5, 0x28c6, 0x28c7,
+  0x2888, 0x2889, 0x288a, 0x288b, 0x288c, 0x288d, 0x288e, 0x288f,   0x28c8, 0x28c9, 0x28ca, 0x28cb, 0x28cc, 0x28cd, 0x28ce, 0x28cf,
+  0x2890, 0x2891, 0x2892, 0x2893, 0x2894, 0x2895, 0x2896, 0x2897,   0x28d0, 0x28d1, 0x28d2, 0x28d3, 0x28d4, 0x28d5, 0x28d6, 0x28d7,
+  0x2898, 0x2899, 0x289a, 0x289b, 0x289c, 0x289d, 0x289e, 0x289f,   0x28d8, 0x28d9, 0x28da, 0x28db, 0x28dc, 0x28dd, 0x28de, 0x28df,
+  0x28a0, 0x28a1, 0x28a2, 0x28a3, 0x28a4, 0x28a5, 0x28a6, 0x28a7,   0x28e0, 0x28e1, 0x28e2, 0x28e3, 0x28e4, 0x28e5, 0x28e6, 0x28e7,
+  0x28a8, 0x28a9, 0x28aa, 0x28ab, 0x28ac, 0x28ad, 0x28ae, 0x28af,   0x28e8, 0x28e9, 0x28ea, 0x28eb, 0x28ec, 0x28ed, 0x28ee, 0x28ef,
+  0x28b0, 0x28b1, 0x28b2, 0x28b3, 0x28b4, 0x28b5, 0x28b6, 0x28b7,   0x28f0, 0x28f1, 0x28f2, 0x28f3, 0x28f4, 0x28f5, 0x28f6, 0x28f7,
+  0x28b8, 0x28b9, 0x28ba, 0x28bb, 0x28bc, 0x28bd, 0x28be, 0x28bf,   0x28f8, 0x28f9, 0x28fa, 0x28fb, 0x28fc, 0x28fd, 0x28fe, 0x28ff,
+}
+
+-- https://stackoverflow.com/questions/7983574/how-to-write-a-unicode-symbol-in-lua
+do
+  local bytemarkers = { {0x7FF,192}, {0xFFFF,224}, {0x1FFFFF,240} }
+  function utf8(decimal)
+    if decimal<128 then return string.char(decimal) end
+    local charbytes = {}
+    for bytes,vals in ipairs(bytemarkers) do
+      if decimal<=vals[1] then
+        for b=bytes+1,2,-1 do
+          local mod = decimal%64
+          decimal = (decimal-mod)/64
+          charbytes[b] = string.char(128+mod)
+        end
+        charbytes[1] = string.char(vals[2]+decimal)
+        break
+      end
+    end
+    return table.concat(charbytes)
+  end
+end
+
+-- testing for glyphs
+--? for _, val in ipairs(glyph) do
+--?   window:mvaddstr(10, 10, utf8(val))
+--?   window:mvaddstr(10, 20, " ")
+--?   curses.getch()  -- just check for menu keys
+--?   sleep(0.1)
+--? end
+
+
+-- convert a chunk of grid into a number
+function grid_char_to_glyph_index(g)
+  return g[1][1]    + g[2][1]*2  + g[3][1]*4  + g[4][1]*8 +
+         g[1][2]*16 + g[2][2]*32 + g[3][2]*64 + g[4][2]*128 +
+         1  -- 1-indexing
+end
+
+
+function render(window)
+  window:clear()
+  for line=1,lines do
+    for col=1,cols do
+      window:addstr(utf8(glyph[grid_char_to_glyph_index(grid_char(line, col))]))
+    end
+  end
+  curses.refresh()
+end
+
+-- test single iteration of render
+--? grid[1][1] = 1
+--? grid[2][1] = 1
+--? print_grid_char(window, grid_char(1, 1))
+--? window:mvaddstr(10, 10, grid_char_to_glyph_index(grid_char(1, 1)))
+--? window:mvaddstr(10, 20, string.format("%x", glyph[grid_char_to_glyph_index(grid_char(1, 1))]))
+--? window:mvaddstr(10, 30, utf8(glyph[grid_char_to_glyph_index(grid_char(1, 1))]))
+--? curses.getch()
+
+-- test render
+--? grid[10][11] = 1
+--? grid[10][12] = 1
+--? grid[10][13] = 1
+--? 
+--? while true do
+--?   render(window)
+--?   curses.getch()  -- just check for menu keys
+--?   sleep(0.1)
+--? end
+
+-- step
+function state(line, col)
+  if line < 1 or line > table.getn(grid) or col < 1 or col > table.getn(grid[1]) then
+    return 0
+  end
+  return grid[line][col]
+end
+
+function num_live_neighbors(line, col)
+  return state(line-1, col-1) + state(line-1, col) + state(line-1, col+1) +
+         state(line,   col-1) +                      state(line,   col+1) +
+         state(line+1, col-1) + state(line+1, col) + state(line+1, col+1)
+end
+
+--? grid[10][11] = 1
+--? grid[10][12] = 1
+--? grid[10][13] = 1
+--? window:mvaddstr(10, 10, num_live_neighbors(10, 12))
+--? curses.getch()
+
+function step()
+  local new_grid = {}
+  for line=1,table.getn(grid) do
+    new_grid[line] = {}
+    for col=1,table.getn(grid[1]) do
+      local n = num_live_neighbors(line, col)
+      if n == 3 then
+        new_grid[line][col] = 1
+      elseif n == 2 then
+        new_grid[line][col] = grid[line][col]
+      else
+        new_grid[line][col] = 0
+      end
+    end
+  end
+  grid = new_grid
+end
+
+grid[83][172] = 1
+grid[83][173] = 1
+grid[84][173] = 1
+grid[84][174] = 1
+grid[85][173] = 1
+
+while true do
+  render(window)
+  curses.getch()  -- just check for menu keys
+--?   sleep(0.1)
+  step()
+end
diff --git a/src/Makefile b/src/Makefile
index 36bb294..c88fb28 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -97,7 +97,7 @@ generic:
 	$(MAKE) all MYCFLAGS=
 
 linux:
-	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX MYLIBS="-Wl,-E -ldl -lncurses"
+	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX MYLIBS="-Wl,-E -ldl -lncursesw"
 
 macosx:
 	$(MAKE) all MYCFLAGS=-DLUA_USE_LINUX
diff --git a/src/lua.c b/src/lua.c
index b92204f..8d57a94 100644
--- a/src/lua.c
+++ b/src/lua.c
@@ -5,6 +5,7 @@
 */
 
 
+#include <locale.h>
 #include <ncurses.h>
 #include <signal.h>
 #include <stdio.h>
@@ -402,6 +403,7 @@ int main (int argc, char **argv) {
     l_message(argv[0], "cannot create state: not enough memory");
     return EXIT_FAILURE;
   }
+  setlocale(LC_ALL, "");
   initscr();
   start_color();
   draw_menu(L);